Conventional reactors for carrying through different kinds of chemical reactions in a batch-wise manner have usually been in the shape of a vessel of a suitable dimension into which the reactants are poured and allowed to react during a predetermined reaction time. The vessel is usually provided with mixing means. If it is necessary to heat or cool the reactants the vessel may have been provided with a heating or cooling mantle or heating or cooling coils, which are immersed in the reactants. The heat transfer characteristics of such an arrangement is poor as well as the mixing.
Another type of reactor making it possible to carry through reactions continuously consists of tube reactors comprising tubes of suitable length, through which the reactants are made to flow. Such an arrangement gives possibility to control the holding time especially at turbulent conditions. If the reactants should be heated or cooled, the tube may be surrounded by a shell, through which heating or cooling medium is forced to flow.
Recently, plate reactors often called micro-reactors for carrying through catalytic reactions have been presented to the market. These micro reactors are often used in connection with fuel cells. Such a micro-reactor is described for example in EP 1 091 800, which shows a compact, catalytic reactor built up of piled textured plates forming reaction spaces and heat-bearing spaces. The texture may be in the form of channels aiming at a good distribution of the reaction liquid.
This type of reactors may also be used on a larger scale.
Flow directing inserts are known in many connections in order to divide a flow and to ensure that the flow direction is constantly changed. These inserts consist of different kinds of packing material, which is available in different materials and configurations. WO 01/94006 describes an example of a tube reactor of this kind with reaction tubes with modular packing that create turbulence in order to promote fluid flow through the packing material.